Snap latch plug



W. S. WAT

SNAP LATCH PLUG Get. 5, 1954 2 Sheets-sheaf 2 Filed Feb. 14, 1951 A oRNEYs:

Patented Oct. 5, 1954 SNAP LATCH PLUG William S. Watts, Harrisburg, Pa., assignor to Aircraft Marine Products, Inc., Harrisburg, Pa.

Application February 14, 1951, Serial No. 210,839

3 Claims.

This invention relates to electrical connector plugs and more particularly to spring latch hand plugs that hold against pressure on the head but are readily withdrawn by a pull from the rear.

A primary object of this invention is to provide in a latch plug of the type wherein a pull on the wire acts directly to Withdraw the latch and allow removal of the plug, a more rugged and simpler latch mechanism than has heretofore been found most satisfactory. A further object is to provide a positively acting latch that will not damage the plug board or panel when being inserted and withdrawn, and which will not itself be damaged by force applied to the plug or the wire. Still further objects are to provide a superior spring latch plug that is simple, inexpensive and easy to mass produce. Other and further objects will become apparent during the course of the following description and from the appended claims.

The principles of the invention will be more readily perceived in connection with the following detailed description of a specific illustrative embodiment and from the accompanying drawings in which:

Figure 1 is a sectional View of a typical installation showing a plug latched in place against the spring pressure and one partly withdrawn;

Figure 2 is a sectional view along line 2-2 of Figure 1 showing the latch detail;

Figure 3 is a plan view of the plug assembly;

Figure 4 is a sectional view along line 4-4 of Figure 3.

Figure 5 is a plan view of the segment 55 of Figure 4;

Figure 6 is a section along line 6-45 of Figure 5;

Figure 7 is a section along line 'll of Figure 6.

According to the present invention a small approximately rectangular opening i is cut in the side of a bullet shaped plug shell l2. An actuating spring I l (Figure 4) with tail I6 is positioned within the shell so that latch I8, which is formed as an integral part of said spring, will project through opening Hi to engage the panel board 20 (Figure 1), or other receptacle through which the plug is to be inserted. Spring I4 is secured (Figures and 6) to one end of a terminal 22, e. g., by crimping the terminal thereon. The other end of the terminal is crimped to wire 24 to engage and make electrical connection therewith. An insulation sleeve 26 is shown but is not essential to this invention. A prong 28 is provided to engage latch l8 when it is withdrawn to prevent the entire spring and latch from being freed from the plug shell.

The top of the latch is beveled (32, Figure 4) to facilitate withdrawal and insertion of the plug.

In operation, on inserting the plug, latch I8 is readily depressed by cam action of its sloping outer face, yet it snaps back out so that normally it projects through opening I0 sufficiently to engage the border of the receptacle in the plug board (as shown in Figure 1). Latch I8 acts as a short compression member between point IS on the plug shell and the corner of the hole in the receptacle board and. prevents the plug being forced out by pressure from contact spring 30. The embodiment shown will stand up to pounds pressure on its head without releasing or damaging the plug or latch. To release, the latch wire 24 is pulled, which pulls the actuating spring, tending to bring it to a straight line between the end of terminal 22 and the edge 34 of the opening H] which, together with the camming action of the latch itself against the receptacle, withdraws the latch to the dotted position shown in Figure 4. The latch now clears the plug board and the plug may be removed.

As the latch is withdrawn it engages prong 28 since it is of an inverted U or tubular shape. This prevents the spring and wire from being pulled down into the plug entirely.

Various arrangements and applications of the invention will suggest themselves to those skilled in the art and such arrangements and applications as fall within the spirit of the invention are intended to be covered by the appended claims.

I claim:

1. A spring latch plug comprising a plug shell having an opening in the side thereof, a terminal slidably mounted in said shell and adapted to engage and make electrical connection with a wire, a flexibleactuating spring extending longitudinally within said shell secured to said terminal, a latch carried by said spring and projecting through said opening, and an extension on said spring extending beyond said latch into engagement with the side of said plug shell opposite said latch to provide a forward support for said spring and latch assembly.

2. A latch plug comprising a shell, an opening therein, a latch projecting therethrough, a curved actuating spring connected to said latch and extending laterally as well as longitudinally from both ends of said latch, means for pulling said spring in a direction parallel to the axis of the plug so as to withdraw said latch laterally toward the center and allow removal of said plug, said pulling means also comprising means for making electrical contact with said plug.

3. An apparatus as described in claim 2 wherein said means comprise a sleeve in the open end of said shell, crimped to said spring and adapted to be connected to a wire so that a pull on said 10 wire will withdraw said latch.

References Cited in the file of this patent Number Number UNITED STATES PATENTS Name Date Maag-Eckenfelder June 28, 1932 Lake Mar. 15, 1938 Modrey Sept. 9, 1947 FOREIGN PATENTS Country Date Switzerland Apr. 16, 1935 Switzerland Feb. 16, 1943 

